Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: humbucker on 30 June 2014, 11:13:35

Title: Irmscher Sport Star staggered fitment tyre size
Post by: humbucker on 30 June 2014, 11:13:35

Hey y'all. Anyone know what the correct/recommended tyre size is for 18-inch Irmscher Sport Stars (the proper Omega ones, ET30 with the staggered fitment / 9-inches at the rear (none of this Vectra nonsense ;) ). Cheers.  :y

Title: Re: Irmscher Sport Stars staggered fitment tyre size
Post by: humbucker on 30 June 2014, 11:15:21

I did look here, but no conclusive answer  ???

http://www.omegaowners.com/forum/index.php?topic=57045.5 (http://www.omegaowners.com/forum/index.php?topic=57045.5)

Title: Re: Irmscher Sport Stars staggered fitment tyre size
Post by: humbucker on 30 June 2014, 11:18:25

Ah, panic over, looks like I've answered my own question.  :y

http://www.irmscher.de/abe/de/7_61_10_490_491.pdf (http://www.irmscher.de/abe/de/7_61_10_490_491.pdf)

Title: Re: Irmscher Sport Star staggered fitment tyre size
Post by: 05omegav6 on 30 June 2014, 11:24:31

Without looking... 245/40/18 for the fronts and 265/35/18 for the rears :y

Title: Re: Irmscher Sport Star staggered fitment tyre size
Post by: chrisgixer on 30 June 2014, 12:13:16

I run 245 40 18 front. Sc3mo or Dunlop sort max tt. There are some minor rubbing issues where the outside edge meats the wheel arch liner on full compression though. So minimal camber helps. ...,you may prefer 235 wide instead. Both recommended sizes according the tuv docs.

Rear is 265 35 18. Sc3 mo again on mine. But there is loads if room in the rear wheel arch. Is there another size that fits too though?

Title: Re: Irmscher Sport Star staggered fitment tyre size
Post by: 05omegav6 on 30 June 2014, 12:17:09

I have no rubbing issues with 245's but the Stila wheels are an ET33 offset, and the car isn't lowered :-\

Title: Re: Irmscher Sport Star staggered fitment tyre size
Post by: TheBoy on 30 June 2014, 17:48:56

Obviously, you can't put 265 tyres on the narrow wheel, so for rear, depends on the rims

Title: Re: Irmscher Sport Star staggered fitment tyre size
Post by: chrisgixer on 01 July 2014, 09:26:19

Quote from: Taxi Al on 30 June 2014, 12:17:09

I have no rubbing issues with 245's but the Stila wheels are an ET33 offset, and the car isn't lowered :-\

I've had et38 on, and with a tyre with big rim protection, they have been known to rub the shock upright in corners. Where as et30 are the opposite end of the scale, sitting 8mm further outboard, hence the wheel arch liner comes into play, although 245 in the bigger fitment, with rim protection adding further width towards the liner as well. Although increasing camber to 1.15 as Wim recommend for sports suspension leans the wheel in at the top, which sorted the rubbing for me.

My drivers side liner is battered and deformed though, from an incident with range rover. So rubbing noises may persist more as a result. Its on the list ::)


Aaaaaanyway. Point is et33 are in the middle of those two extremes so you should be fine. Your ride height is also way above standard too. Then add in Irmscher lowered springs on mine at 30mm below standard.....

Title: Re: Irmscher Sport Star staggered fitment tyre size
Post by: chrisgixer on 01 July 2014, 09:30:14

Quote from: TheBoy on 30 June 2014, 17:48:56

Obviously, you can't put 265 tyres on the narrow wheel, so for rear, depends on the rims

Yes 265 on a 9j rim. 245 being widest on 8j.


(Why we have to have a j instead on inches I don't know)

Title: Re: Irmscher Sport Star staggered fitment tyre size
Post by: aaronjb on 01 July 2014, 10:00:54

The J designates the bead profile, there is also JJ, K, JK, B, P and D (though I've never seen one)

http://www.carbibles.com/tyre_bible_pg4.html